Noninvasive, in vivo imaging of animals is an important tool in biomedical research. The Center for Gamma- Ray Imaging (CGRI) at the University of Arizona was established based on NIH funding to develop ultra-high resolution SPECT imaging systems, with sub-millimeter spatial resolution for small-animal applications. We seek support to organize the first Workshop on Small-Animal SPECT to be held at the Westward Look Resort in Tucson, Arizona on January 14-16, 2004. The overall goal of the meeting is to promote information exchange and collaboration between the research groups developing systems for small-animal applications. Furthermore, the workshop intends to stimulate the use of SPECT systems in the areas of oncology, cardiology, and gene therapy. We anticipate 75-100 attendees. This number was determined from a small survey previously conducted within the small-animal imaging community. The program will include short-course presentations by the faculty of CGRI and selected oral presentations by the attendees. Topics include: biomedical significance of small-animal imaging, overview of detector technologies including scintillation cameras and semiconductor arrays, imager design and data acquisition systems, animal handling and anesthesia issues, objective assessment of image quality, and system modeling and reconstruction algorithms. The grant will assist with the logistic support of organizing the workshop and provide travel support for about 10 graduate students and post-docs.